The present application claims priority to European Patent Application No. 01 103 271.1 filed Feb. 12, 2001, the disclosure of which is hereby incorporated herein by reference in its entirety.
The present invention relates to an apparatus for mounting and cooling a flat screen.
It can be referred to a flat screen if the ratio of diagonal of the screen to the depth of the screen unit is approximately 10:1 or more. Flat screens of this type are gaining ground basically because of the fact that space and weight can be reduced compared to the conventionally used apparatus that use electron tube technology, and these flat screens will soon supersede conventional screens. The two most important types of flat screens are on the one hand LCD screens and on the other hand screens using plasma displays, hereinafter abbreviated as plasma screens.
Both types of flat screens generate heat when being operated, which must be dissipated from the surrounding housing as quickly and safely as possible. A significant amount of heat is in particular generated by plasma screens because of the high voltages that are required to transfer the respective gas mixture into the light emitting plasma state.
The cooling of plasma screens is conventionally performed by means of a plurality of active fans. During unsupervised operation, a failure of one or a plurality of fans may lead to the destruction of the heat generating units or of the entire screen. Moreover, the fans need additional space within the housing provided for the flat screen, thus increasing the total depth thereof. Moreover, the use of fans leads to side noises, which are perceived to be unpleasant in domestic use (for instance as a television set) and when using the apparatus professionally (for instance as a supervision monitor).
Thus, it is the object of the present invention to provide an extremely small dimensioned apparatus for mounting and cooling a flat screen, by means of which the heat generated can be very safely discharged without the generation of side noises, simultaneously reducing maintenance and repair work to a minimum.
This object is achieved by an apparatus for mounting and cooling a flat screen during operation, comprising a housing for accommodating the flat screen and heat generating electric and electronic units, and comprising at least one thermal bridge for conducting the heat generated by these units to a heat conductive plate arranged on a rear side of the housing, said plate being equipped with a profile for faster cooling of the plate, wherein the plate forms a rear wall of the housing, the profile on the rear wall of the housing forms a plurality of chimney-like cavities each comprising a lower end portion and an upper end portion, wherein in the lower end portion at least one opening for supplying cool air into the respective cavity is provided, and in the upper end portion at least one outlet opening for discharging heated air from the cavity to the atmosphere is provided, and the rear wall of the housing comprises a plurality of through holes arranged in the area of the cavities which serve for supplying and discharging air into or out of a space arranged between the heat generating units and the rear wall.
The apparatus according to the invention for mounting and cooling a flat screen during operation comprises a housing for accommodating a flat screen and possibly further heat-generating electric and/or electronic units, moreover, thermal bridges for conducting the heat generated at least by the flat screen including its electronic control components to a heat conductive rear wall of the housing. The rear wall is provided with a plurality of chimney-like cavities, which each have on their lower end portion at least one opening for supplying cool air into the respective cavity, and at least one outlet opening in the upper end portion of each cavity for discharging heated air to the atmosphere. It is ensured thereby that significant amounts of heat can be transported to the outside without taking the risk of a failure of the cooling apparatus.
In order to be able to conduct the main part of the heat immediately to the atmosphere by the conduction of heat, a thermal bridge made of heat conductive material oriented towards the rear wall of the housing is preferably mounted on at least one position of a printed circuit board attached at the housing frame, with a plurality of heat conductive components of the flat screen being arranged on the printed circuit board, wherein the thermal bridge engages the rear wall during the operative condition of the screen.
For the additional cooling by an exchange of heat, the rear wall of the housing preferably comprises a plurality of through holes, which serve for supplying and discharging air into or from a space arranged between the printed circuit board and the rear wall.
In order to be able to easily conduct the air generated during operation and located between the printed circuit board and a glass plate arranged on the front end side, at least one channel is preferably provided through which the air may reach the space between the printed circuit board and the rear wall.
In order to obtain a more flexible configuration of the apparatus, it is advantageously provided that the profile be screwed onto the rear wall.
In order to achieve that the apparatus may easily fulfil the safety regulations regarding the maximum permitted outer temperature of apparatus, the chimney-like cavities each have a preferably cartridge-like cross section having an end rounded towards the outside.
The individual chimney-like cavities are preferably spaced apart so that an additional air cooling of the connection surfaces in the spaces between the cavities and of the walls of the U-shaped cavities takes place.
The housing frame and the rear wall are preferably formed of extruded aluminium profiles, which have low weight and can be easily worked.
In order to obtain stability while keeping the apparatus optically aesthetic, the frame pieces are advantageously joined by laser welding.
Further details, features and advantages of the present invention can be derived from the following description with reference to the accompanying drawings.